Drupal can use a pre-set theme or a customized one.  In order to keep things simple for now I will start with the default called "Bartik".  Here is regions that are setup in that theme.

Secondary Menu




Header




Primary Menu




Highlighted




Featured Top




Breadcrumb





Content
Sidebar First

Sidebar Second








Featured Bottom FirstFeatured Bottom SecondFeatured bottom third




Footer FirstFooter SecondFooter thirdFooter fourth




Footer fifth